Why maligned all-rounder must be in Test side

ENGLAND legend Michael Vaughan believes Australia must invest in dumped all-rounder Mitchell Marsh or risk defusing one of their biggest weapons ahead of the Ashes series.

Marsh was controversially dropped for the first Test against India, just weeks after coach Justin Langer handed him the vice-captaincy role.

After a lean trot with both bat and ball, Marsh was overlooked for a pure batsman, with Peter Handscomb earning a Test recall over the out-of-favour all-rounder.

But former England captain Vaughan says the only way to unlock Marsh's potential is persistence.

"Australia have to buy into Mitchell Marsh," said Vaughan after day one at the Adelaide Oval.

"If he's going to be around the Test match team for a few years he needs a run in the side - I would have played him this week.

"(He) is certainly worth persisting with and I think the only way he'll get better and be a real prominent member of the Test team is to play a run of games.

"When you come to England in a few months time his style of bowling and play will be invaluable."

Mitch Marsh struggled against Pakistan with both bat and ball. Picture: AAP

Marsh scored just 30 runs in four innings against Pakistan in the UAE and his bowling figures weren't much better, taking just the two wickets for the series.

But while Vaughan acknowledges Marsh needs to work on his game, the Ashes-winning captain says he will only develop out in the middle.

"I would have played him this week," Vaughan said. "I do think in these type of conditions you need five bowling options and I think he's the kind of cricketer if they (Australia selectors) buy time with him and give him a run of games he can get better.

"I like his batting, he's quite rigid and he needs to work against spin a bit better. His bowling is certainly worth persisting with."